1. Field of the Invention
The invention relates to motor vehicles, and refers more specifically to curvilinear flexible drive structure for a motor vehicle having front or rear mounted transversely, or in line mounted, power packs for providing selectively activated or full time four wheel drive for the motor vehicle, or for providing conventional two wheel drive for the motor vehicle, and/or strategically located selectively or permanently activated torque limiting devices which are part of the motor vehicle's drive structure.
2. Description of the Prior Art
In the past, drive structures for motor vehicles having in line (North/South) front mounted power packs and rear wheel drive have included an elongated rigid drive shaft extending from the front mounted, in line, power pack to a rear differential and transversely extending rear half axles between the rear differential and the rear wheels.
Conventional front or rear wheel drive structures are also known wherein the power packs are positioned at the front of the vehicle for front wheel drive and at the rear of the vehicle for rear wheel drive vehicles. With such structures, the power packs are usually mounted transversely of the vehicles (East/West) and the wheels are driven directly through transaxles. In some such configurations, off set gearing driven by the differential gear has been utilized to drive the wheels at the same end of the vehicle that the power pack is mounted in.
Prior four wheel drive vehicles have alternatively included permanent four wheel drive systems or selectively actuated four wheel drive systems. With the selectively actuated four wheel drive systems, one of the vehicle's front or rear wheel sets are additionally driven only when a four wheel drive function is selected. Currently, conventional selectively actuated four wheel drive systems may include means for changing from two to four wheel drive while the vehicle is either standing still or moving. More recently, these systems have included conventional rotational differentiation combined with torque compensation, also called torque split, between front and rear drives as well, in some cases, as between left and right hand opposite wheels of one or more wheel driving axles.
The only known flexible cable drive structure for a motor vehicle is found in the U.S. Pat. No. 1,897,452 to West. In the West structure, a multistrand cable is utilized within a rigid longitudinal sleeve between a front mounted, North/South, vehicle power pack and the rear differential of the motor vehicle. A similar multistrand cable within a rigid cylindrical sleeve or transverse, East/West, housing is utilized to drive the two rear wheels of a four wheel motor vehicle from the rear differential by West.
West utilizes the multistrand cables in their linear configurations for their wind up capabilities to reduce torsional shock imparted to or coming from a rigid, longitudinal drive shaft and rear wheel axle shafts. West neither utilized nor makes any reference to the flexibility of his multistrand cables for permitting curvilinear installations of his drive shaft, including a curvilinear cable and sleeve, around underbody structure obstructions, exhaust components or gas tank, and improved drive line packaging for the sake of eliminating the drive line tunnel or obtaining a lower floor while maintaining a desired ground clearance or minimizing floor plan structure tooling changes when adding rear wheel drive to a front wheel drive existing production vehicle.